Spring-clip.



PATENTBD MAY. 31, 19o4.j

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APPLICATION FILED 00T 17 1903 N0 MODEL.

UNITED STATES y retented Meg-.31, 1904.

PATENT OFFICE.

' i SPRING-CLIP.

SPECIFICATION forming part ef Lettere Patent No. 761,533, dated Mey31,1904. l Application filed October 17, 1903. Serial No. 177,460. (Nomodel.) i

To a/ZZ whom t Wray concern;I

Be it known that I, JOHN S. MCKE, a'citi- Zen of the United States ofAmerica, residing at Pittsburg, in theA county ofAllegheny and State ofPennsylvania, have invented certain new and usefulImprovements inSpring-Clips, of which the following is a specification, reference beinghad therein to the accompanying drawlngs.

Thisinvention relates to certain new and useful improvements inspring-clips, such as are used in connection with switches,circuitbreakers,` and otherdevice's used for openingl and closingelectric circuits; and the invention is particularly designed to beemployed in connection with that lform of switch, circuit-breaker, orother analogous device using two or more blades at each pole.

The object of the present invention is to provide means for eliminatingthe danger of blistering the middle clip or,V inside contactsurface ofthe blade at the time of breaking the circuit, which blisteringfrequently prevents the rengagement of the blade with its clip orcontact.

With the use of laminated blades in switches. circuit-breakers, and thelike it frequently thereby formed causes the blistering or beading ofthe middle clips in such a manner as to prevent the reengagement of theblades with their clips.

. It is the object of my present invention to so construct these clipsthat in event of any' blistering or beading taking place the same willbe on the outside clips or contacts, but

will not interfere with the rengaging of the blades with their clips orcontacts.

Briefly described,l my invention comprises a construction which causesthe arc when formed to be between the blades and the outside clips orcontacts, and this result may be accomplished in either of two ways-thatis,

ence is had to the accompanying drawings, forming a part of thisspecification, and wherein like numerals of reference indicatelike partsthroughout the several views, in 'which- Figure l is a detail plan Viewof the ordinary form of switch employing laminated blades. Fig. 2 is alike view of the ordinary form of circuit-breaker employing laminatedblades.

Fig. 3 is an end view of a switch, showing the laminated blades incross-section and employed in connection with my improved spring clipsor contacts. Fig. 4 is an end view of a circuitbreaker employed inconnection with my improved spring clips or contacts. Fig. 5 is anelevation of one of the spring-clips, showing the laminated blades incross-section, illustrating how the blades have passed out'of engagementwith the middle clips before passing out of engagement with the outsideclips. Fig. 6 is an elevation of a part of acircuitbreaker, illustratingthe same principle. Fig. 7 is a sectional view of a modified form ofconstruction, showing the middle blades of the pole of less width thanthe outside blades. Fig. 8' is a sectional view of the sameconstruction, illustrating how the middle blades pass outof engagementwith the middle clips prior'to the outer blades leaving engagement withtheir clips or contacts.

My invention resides entirely in the provision of novel means for thepreventing of the arc being formed between the laminated blades and theinside clips or contacts, and I may accomplish this result by making themiddle spring clips or contacts 1 of shorter length than the outsideclips or contacts 2, as illustrated in connection with the switch shownin Figs. 1, 3, and 5.

It is to be understood that the invention is applicable only to that"form of switch, circuit-breaker, or analogous device employing laminatedblades for each pole, and, as illustrated in Fig. 5, it is to beobserved that the laminated blades 3 have entirely passed out of contactwith the middle clips or contacts l tween blades and clips l is brokenno arc will be formed between the said blades and the said middle clipsor contacts l, said arc being formed entirely between the outside clips2 and the blades 3. This arcing between the blades and the clips has atendency to blister the clips, often forming' a bead thereon ofsuflcient size to prevent the reentry of the blades into engagement withthe clips. With my improved construction, however, if this bead isformed it is'on the outside clips 2 and no obstruction is presented tothe blades reengagingwith thevmiddle clips 1, and by reason of the beadbeing formed on the outside clips these are free to spring outwardly, asmay be required or necessary to force the blades into their engagingposition.

In Figs. 2, 4:, 6 I show the same principle in connection with acircuit-breaker wherein the middle clips 5 are made considerably shorterthan the outside clips 6, the laminated blades 7 passing out ofengagement with the inside clips 5 prior to their passing out ofengagement with the outside clips 6. 251

In Figs. 7 and 8 I show a modified form of construction by means ofwhich the same result may be obtained, the clips 8 being of the samelength, but the outside blades 9 of each pole being of greater widththan the intermediate blades l0. Consequently as the device is operatedto break the circuit the blades lO pass out of engagement with theintermediate or middle clips prior to the passing of blades 9 out ofengagement with the outside clips, thus causing any arcing which may bedone to ble between the outside blades and the outside c ips.

Itis to'be noted that by the elimination of the possibility of thecentral clip burning the blades of the switch or other device may beplaced much closer together than in the ordinary construction, enablingme to make a neater, smaller, and stronger switch. lVith the shorteningof the middle clips or contacts or the varying in the width of theblades in accordance with the construction shown in Figs. 7 and 8 it isto be observed that not only is the danger of blistering the middleclips eliminated, but also the danger of blistering the inner contactingsurfaces of the blades, as these contact-points are free before linalcontact is broken on th'e outside clip, and the resultant burning orarcing on the outside clips is not detrimental to the circuit beingagain closed, as is the case where the clips are all of the same heightor the blades of a uniform width.

It will be obvious that various slight changes may be made in thedetails of construction without departing from the general spirit of myinvention.

Having fully described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

1. An electric switch containing a switchblade comprising two parallelblades, and acooperating clip consisting of two outer parts and shortercentral contact part.

2. An electric switch having laminated switch-blades andspring-contacts, said switchblades and said contactsconstitutingseparable contact members the inner sections oi one el saidmembers having less contact-surface than the outer sections of the same.

3. A switch or analogous device composed of two members one movable inrelation to the other, one of said members being provided. with contactparts composed of central laminac and outside laminze the other memberhaving blades adapted to enter between said laminated contact parts, thecontacting surfaces at both sides of one of said members being inadvance of the contacting surfaces at the middle of the same.

In testimony whereot` I aiix my signature in the presence of twowitnesses.

JOHN S. MCKEE.

Witnesses:

A. M. WILSON, E. E. POTTER.

